One of the problems encountered in conventional waterbed design is the presence of wave motion within the waterbed mattress. A conventional waterbed comprises a water retaining bladder, generally vinyl, supported along its sides by a rigid frame. Where there is no provision for damping of wave motion within the mattress, movement of a person on the water-retaining bladder will generate waves within the bladder which reflect off the sides of the frame causing standing waves within the bladder at a resonant frequency depending on the volume of the bladder. This wave action is disturbing to the individual sleeping on the mattress.
Consequently, various means for damping the wave action have been attempted. One common approach is to provide floating inserts of one form or another within the mattress to dampen wave motion. These may be floating baffles, plastic foam sheets or a floating mat of non-woven polyester fibre which is fixed with acrylic binder. A typical example of such a floating fibre mat is formed of 45 denier non-woven polyester fibres bound together with acrylic resin, with the fibres oriented both horizontally and vertically prior to binding. Such a fibre mat is sufficiently porous that water can flow through it.
It is desirable to anchor such floating structures to the bottom of the mattress. Otherwise the inserts can shift, fold or ball up when the mattress is emptied, moved or even during normal use. Previously such anchoring has been accomplished simply by attaching one end of a vinyl tether to the insert and welding the other end of the vinyl tether directly to the bottom of the mattress. This shortens the life of the mattress since it places added strain on the seams of the mattress and eventually a leak will be created in the mattress.
There is therefore a need for a means of anchoring floating waterbed mattress inserts which reduces the problem of stress on the seams of the mattress.